This invention relates to an apparatus and method for dispensing soft serve food products such as ice creams, yogurts, sherbets, and other frozen dessert confections.
Soft serve frozen confections are widely used in the food industry and have a broad customer appeal. Although ice creams are the most widely known product dispensed in a soft serve form, an expanding market based on alternative frozen confections such as yogurts also exists. A soft serve confection is dispensed by extrusion into an edible cone or other suitable container, and is generally intended for immediate consumption.
A soft serve confection can be easily extruded from the dispensing apparatus in a variety of patterns or shapes. A common manner of dispensing a frozen confection consists of extruding a continuous ribbon or rod that can be coiled on itself to form a cone having a beehive shape. Soft serve confections ideally will have sufficient strength to retain the extrudate shape for a period of time, even when subjected to changes in orientation such as would occur during consumption.
The dispensing temperature of the soft serve frozen confection typically ranges from about 16.degree. F. to 21.degree. F. This temperature range is critical, with lower temperatures being characterized by difficulties in extrusion of the soft serve frozen confection, mechanical hardness, and inferior taste quality due to the adverse reaction of taste buds to a low temperature frozen confection, often resulting in a "burning" sensation. Temperatures higher than the normal soft serve confection dispensing range result in a low viscosity product with undesirable rheological characteristics that do not permit retention of the extrudate shape and are unsuitable for later processing such as dipping in chocolate or crushed nutmeats.
Because of the critical narrow temperature range for soft serve frozen confections it is not feasible to transport the frozen confections at their normal dispensing temperature.
To overcome this problem, the food service industry presently utilizes on-site production of the soft serve frozen confections. The soft serve confection can be shipped from the manufacturer to the food product retailer as a powder, a refrigerated liquid, or in a frozen state. If the confection is not in a liquid state, it is converted to the liquid state at the site of the food product retailer. For example, a confection shipped in the frozen state is allowed to completely thaw to liquid form, or water is added to the powdered form. This liquid is converted on-site to a soft serve frozen confection by an agitated freezing process in a soft serve frozen confection dispenser.
Although on-site production of the soft serve frozen confection permits the successful manufacture and service of soft serve frozen confections, the method does present some problems of its own. The machinery necessary for on-site production is complicated and expensive. Scraper blades that agitate the frozen confection during its on-site formation require sharpening or replacement, and inadvertent freeze-up of the machinery is a continual worry. The cost in electricity for operating the freezing unit is substantial, and special heavy duty electric wiring may be necessary to handle the power requirements of the freezer. Because of the agitation process, addition of extra elements, such as nutmeats, candies or fruits, to the soft serve confection is normally impossible. Frequent regular cleaning of the parts of the frozen confection dispenser is also necessary to prevent blockage and reduce the chance of bacterial contamination.
A further disadvantage of the on-site production is the increased risk of bacterial contamination presented at each stage of the process. Although the liquid is refrigerated, the chance of bacterial contamination is greatly increased over the frozen form. This danger is increased by the possibility of improper cleaning of the machinery, which could result in a seed culture of bacteria capable of contaminating newly added liquid confection. Additionally, quality control of on-site producers of soft serve confections can be inferior as compared to a central manufacturer, resulting in uneven product appearance, taste, and form.
It is accordingly an object of the present invention to provide a soft serve frozen confection dispenser capable of extruding a soft serve frozen confection and suited for use in a commercial setting.
Another object of the invention is to provide a device for dispensing soft serve confections that is sanitary, mechanically simple, easy to clean, draws small amounts of electric power, and in specific embodiments is capable of portable use.
It is a further object of the present invention to provide a device that is capable of serving a soft serve frozen confection without the formation of undesirable ice crystals in the frozen confection.
Yet another object of the present invention is to provide a device that is capable of dispensing soft serve frozen confections which include extra flavoring ingredients such as fruit or candy pieces.
The present invention accordingly comprises an apparatus and method of providing a soft serve frozen confection dispenser that is capable of dispensing certain products such as yogurt in a soft serve form free of the undesirable characteristics formerly associated with such soft serve yogurt products.
According to the present invention an apparatus and method for dispensing soft serve frozen confections in general, and particularly those confections which are difficult to maintain or prepare in a state suitable for soft serve is provided. In one embodiment, a collapsible container impervious to liquids is adapted to contain a frozen confection. The collapsible container has one outlet of sufficient size to allow extrusion of a frozen confection into an outlet conduit. If large chunks of fruits, candies or nuts are added to the frozen confection, the collapsible container outlet is large enough to permit passage of the chunks. Generally, a one inch diameter outlet will be sufficiently large to permit extrusion of the frozen confection and any contained fruit, nuts, candies or similar additive flavorants into an outlet conduit.
The collapsible container outlet may optionally include an integral attached sleeve that flexibly unwinds in an outlet conduit under the pressure of the extruded frozen confection, and acts as a disposable barrier that prevents contamination of the extruded soft serve frozen confection by the outlet conduit and limits the amount of contact the outlet conduit has with the extruded soft serve frozen confection.
The outlet conduit of the dispensing apparatus is affixable to the collapsible container outlet and is capable of receiving the extruded soft serve frozen confection. The outlet conduit contains a valve that is controllable to limit extrusion of the soft serve frozen confection. For example, the valve can be a rotating action shut-off spigot or a vertical plunger shut-off. If the outlet conduit is constructed of a resilient, flexible material, the valve can be a device that enables constriction of the outlet conduit.
Extrusion of a soft serve frozen confection from the dispensing apparatus can be accomplished with a compression arrangement that exerts compressive forces on the collapsible bag. The compression arrangement must have sufficient force to enable extrusion of the soft serve frozen confection from the collapsible container into the outlet conduit. A bellows, capable of being expanded by air under pressure, is a suitable compression arrangement. Additional suitable compression means, such as hydraulically or mechanically operated pistons may also be used in the present invention.
An air pressure relief valve can either manually or automatically provide air pressure relief for the bellows. Collapsing the bellows enables replacement of an empty collapsible container with a filled replacement collapsible container, and protects the food service worker from any potential hazards that might be presented by a pressurized bellows. As an additional safety feature, in one embodiment of the present invention, the air pressure in the bellows can be automatically relieved upon opening the container door of the soft serve frozen confection dispenser apparatus.
The dispensing apparatus includes a freezer section for maintaining the soft serve frozen confection substantially within the normal soft serve dispensing temperature range of 17.degree. F. to 21.degree. F. Ideally, the freezer section will be sufficiently large to contain replacement collapsible containers filled with soft serve frozen confections as well as maintain the soft serve frozen confection in the dispensing section of the dispensing apparatus within the normal soft serve dispensing temperature range.
The soft serve frozen confection held by the collapsible container in the dispensing section has an ideal dispensing temperature. The dispensing section includes thermal insulation means for maintaining the soft serve frozen confection at a constant ideal dispensing temperature. The maintenance of a constant temperature within the dispensing section inhibits ice crystal formation in the soft serve frozen confection that can result from temperature changes such as are encountered in the cyclic temperature fluctuations that normally result from the duty cycle of a freezing unit. The thermal insulation means can be a layer of foam or other passive thermal insulation which completely or partially surrounds the collapsible containers.